[Meta]: Port away from ILogger

[CarlSchwan]

Current pull requests

• [x] https://github.com/nextcloud/server/pull/31609
• [x] https://github.com/nextcloud/server/pull/31943
• [x] https://github.com/nextcloud/server/pull/31948
• [x] https://github.com/nextcloud/server/pull/40508
• [x] https://github.com/nextcloud/server/pull/43387
• [ ] ...

Current remaining modules to port in server

• [x] lib/{private,public}/Files

Current remaining shipped app to port

• [x] federation https://github.com/nextcloud/server/pull/39018
• [x] encryption https://github.com/nextcloud/server/pull/39065
• [x] federatedfilesharing #39160
• [x] files_sharing https://github.com/nextcloud/server/pull/39169
• [ ] files_trashbin
• [x] files_external https://github.com/nextcloud/server/pull/39480
• [x] dav
• [x] weather_status
• [x] settings
• [x] files
• [ ] workflowengine
• [x] user_status
• [x] user_ldap https://github.com/nextcloud/server/pull/40504
• [x] updatenotification
• [x] twofactor_backupcodes
• [x] theming
• [x] sharebymail

Current issues

• The background job interface exposes ILogger in its public API. We need to deprecate this
• In some places, like the updater. It's helpful to be able to write ILogger:DEBUG instead of 2. We need to look if upstream psr would be interested to add enums for the log levels.

[come-nc]

• [x] https://github.com/nextcloud/server/pull/31775

[come-nc]

• [x] https://github.com/nextcloud/server/pull/31752

[Altahrim]

• [x] #39160

[Altahrim]

• [x] #39169